Detachable tooth cap



1951 E. L. LAUNDER 2,996,816

DETACHABLE. TOOTH CAP Filed Sept. 8, 1958 INVENTOR.

fiZW/E Z ZAaA/QEA AGE/VF United States Patent 2,996,816 DETACHABLE TOOTHCAP Ernie L. Launder, Montebello, Calif., assignor to H. & L. ToothCompany, Montebello, Calif., a corporation of California Filed Sept. 8,1958, Ser. No. 759,812 7 Claims. (Cl. 37-442) This invention has to dowith a structure involving a :ooth cap which is separable or detachablefrom its supporting shank and it is a general object of the invention toprovide such a structure which is simple and inexpensive of manufacture,convenient and quick to operate and which is dependable in operation.

The structure embodying the present invention involves a tooth capapplied to a tip provided on the forward end of a digger tooth shank.The tip of the shank is forwardly convergent or tapered and has flatparallel sides. The cap engages or fits over the tip of the shank and ispreferably provided with a blade like top with a sharpened forward end,with depending cheeks that extend down from the edges of the blade and abottom that extends between and connects the lower edges of the checks.The invention provides retaining means by which the cap is releasablysecured or retained on the tip of the shank.

The connection of a tooth cap to a tip is complicated by roughness ofmanufacture inherent in such parts and by the extreme abuses to whichthe parts are subjected in use. Various fastening structures have beenproposed and used for the purpose of holding a tooth cap in place, itbeing a general objective to yieldingly urge the tooth cap intopressured engagement with the tip This invention provides said pressuredengagement utilizing only the basic elements of the tooth cap structureand without resorting to additional fasteners, such as pins or boltswhich characterize the prior art.

The retaining means of the present invention is characterized by eitherone or both of the checks of the cap being provided with inwardlyextending projections which normally extend into sockets or depressionsin the sides of the tip. The particular cap structure involved is suchas to allow the checks to spread or spring somewhat apart as the cap isbeing arranged on or removed from the tip. In the form of the inventionillustrated the projections are at the inner or rear edge of the cap andguide channels are provided in the sides of the tip, the said channelshaving inclined bottoms to be engaged by the projections so that thechecks are spread by wedging action as the cap is applied to the tip.Further, the parts and elements of the structure involved are soarranged as to impose a substantial amount of deflection upon the cheekswhen the cap is in working position and so that the projections, whichare inclined, are yieldingly urged into pressured engagement with theedge portions of the sockets or depressions.

A general object of the present invention is to provide a toothconstruction of the general character referred to characterized byretaining means that holds the cap on the tip of the shank, which meansis normally yieldingly held engaged so the cap is held on the tipthrough resilience of the cap.

Another object of the invention is to provide a structure of the generalcharacter referred to in which the retaining means involves a permanentprojection or embossment on the inner side of the check of the toothcap, which projection is inclined and is received in a socket providedin the side of the tip.

A further object of this invention is to provide a construction of thegeneral character referred to which serves to efliectively retain atooth cap on a shank without requiring manipulation or deformation ofany part upon assembly of the structure and without requiring additionalPatented Aug. 22, 1961 ice fastening devices likely to become displacedor subject to failure.

The various objects and features of my invention will be fullyunderstood from the following detailed descrip tion of a typicalpreferred form and application of the invention, throughout whichdescription reference is made to the accompanying drawings, in which:

FIG. 1 is a side elevation of a digger tooth and adapter shank, being aview showing the parts and elements as they appear when assembled. FIG.2 is a sectional view taken substantially as indicated by line 2-2 onFIG. 1. FIG. 3 is a view similar to FIG. 1 illustrating the mode ofassembly of the parts and elements, and FIG. 4 is a view with certainparts broken away to show in section and taken as indicated by line 4-4on FIG. 3.

The present invention is particularly practical when employed forsecuring a tooth cap on a shank and in the drawings a simple form of theinvention is shown applied to a common or typical form of digger toothconstruction. In the case illustrated an implement such as a bucket (notshown) is provided with a plurality of digger teeth each of whichinvolves an elongate shank B at the lip A of the bucket and at theforward end portion of which there is a tip C. A tooth cap D is appliedto or engaged over the tip of the shank and releasable retaining means Enormally secures the cap on the tip.

The shank B is shown as an elongate element and the tip C is shown as anintegral extension or continuation of the shank which converges ortapers to a point at 10. The particular tip C illustrated in thedrawings has a flat top 1.1, a flat bottom 12 and flat parallel sides13. The top 11 and bottom 12 converge as they extend forward to cometogether or join at the tip portion 10. The sides 13 may be simple flatparallel parts, as shown throughout the drawings.

The cap D is, in efiect, a jacket or cover that engages over the tip onthe shank and in the case illustrated it involves, generally, a top 15in the form of a blade, sides or checks 16 which depend from the top anda bottom 17 which extends bet-ween and connects the lower edge portionsof the checks.

The blade 15 is a heavy or substantial element that rests on the top 11of the shank tip and which projects forward therefrom and has itsforward end 2% dressed or finished to have the desired digging orcut-ting action. The cheeks 16 are joined to the edge portions of theblade .15 and depend therefrom to occur close to or against the sides 13of the tip. The cheeks cover the sides of the tip where the cap occurson the tip. The bottom 17 extends between or joins the lower edgeportions of the cheeks and engages or bears against the bottom 12 of thetip.

The retaining means provided by the present invention operates to holdor secure the cap D on the tip C and in practicethe retaining means canbe carried out in connection with either one or both of the checks ofthe cap. Since the retaining means when applied to both sides or checkswill be alike I will describe one side only, it being understood thatsuch description is applicable to both sides or checks.

The retaining means involves, generally, an inwardly extendingembossment or projection 30 on the inner side or face 31 of the cheeks16 which projection enters "a socket or depression 32 provided in theside 13 of the tip which is opposed by the cheek. In the form of theinvention illustrated throughout the drawings, the projection 30 of themeans E is an inwardly bent or pressed part in the form of an embossmentcausing a projection at the inner side of the cheek and a depression ordimple at the outer side thereof. The said projection 39 is located ator near the rear or inner edge 35 of the cheeks where it cooperativelyengages with a socket or depression 32 in the side 13 of the tip. In theform of the invention illustrated, the projection 30 of the means Einvolves bending of the wall or cheek "16, as shown, so that it isindented inwardly with a convexly rounded inner face 31. In practice,the projection is circular in form and with the face 31 merged with thewall of the cheek 16. That is, the projection 30 is disposed inwardly asubstantial depth and so that the said face 31 is inclined to merge withthe cheek 16.

The socket or depression 32 in the side 13 of the tip C is tapered orconical in form so that it has a tapered wall 33, as best illustrated inFIG. 2 of the drawings. The socket 32 can be formed in the tip C as bycountersinking with a suitable drill, the wall 33 being disposed atsubstantially the same angle as the face 3 1 of the projection 30, abovedescribed.

With the construction as above described the cap can be applied to thetip when the tip has plain smooth sides 13 which are uninterrupted andare parallel with each other. As the cap is started onto the tip theentering action of the tip by engagement with the projections 30 spreadsthe cheeks and holds them spread until the cap reaches operatingposition at which time the projections 30 enter the sockets 32 allowingthe cheeks to assume a normal operating position. The engagement of theinclined face 31 of the projection with the inclined wall of the socketeffectively retains the cap on the tip until such force is applied as tocause the cheeks to be spread, by a cam action, and the cap to be thenforced off the tip.

In accordance with the invention the cheeks 16 are formed of suchmaterial and are of such wall thickness as to allow for or permit of thedesired movement or spreading action in order to permit of engagementand disengagement of the retaining means E, as hereinabove described. Inthe particular case illustrated the blade 15 is a heavy rigid element,preferably a steel plate, Whereas the cheeks 16 and bottom 17 that forma housing are formed of a relatively thin-walled material, preferablysheet steel and thus affording the desired resilience for operation ofthe cheeks in a manner to allow for engagement and disengagement of theprojections 30 over the tip C and into and out of the sockets 32.

In carrying out the present invention, the blade 15 and the housingformed by the parts 16 and 17 are made of comparatively differentmaterials. That is, when steel is employed in the manufacture of the capof the present invention, the blade material is selected for hardnessand toughness while the housing material is selected for resiliency. Inthe manufacture of the particular tooth cap D illustrated, the blade andhousing are separate elements joined by welding W, and since theseelements are permanently joined together it is necessary to heat treatthem together. Therefore, I employ a material such as, for example,S.A.E. 4142 or S.A.E. 8742 chromemolybdenum steel for the blade 15 and Iemploy a'material such as, for example, S.A.E. 4115 or S.A.E. 8715chrome molybdenum steel for the housing formed by the elements 16 and17. The above mentioned materials, as specified, are brought to the sameheat during heat treatment and as a result the blade is hardened to aBrinell of 514 to 535 while the housing is hardened to a Brinell of 285to 302. As a result of the foregoing selection and simultaneous heattreatment of the material employed, the blade is adapted to hard usagewithout subject to breakage while the housing is adapted to yield underforce and is resilient so as to make effective the means E abovedescribed.

In the structure thus far described the projections'30 of the means Eare engaged over the tip C with some difficulty. That is, the tooth capD cannot be installed in Working position with any degree ofpredetermined facility. Therefore, channels 50 are provided in the sides13 of the tip C, said channels having inclined or pitched bottoms 51which have wedging action upon engagement with the projections 30causing the cheeks 16 to be spread as the cap D is moved to a positionwhere the projections 30 drop or engage into the sockets 32. Thechannels 50 with the inclined bottom faces 51 are provided primarily asa means of facilitating spreading of the cheeks in the course ofengaging the cap with the tip and open forwardly to freely receive theprojections 30. In the case illustrated, the blade 15 overlies the top11 of the tip C in which case it is desirable to rest the blade 15 uponthe top 11 when the cap D is moved rearward into engagement with the tipC, and, therefore, the channels 50 are preferably parallel with the top11 and open at the bottom 12 to receive the projections 30. The bottomfaces 51 of the channels 50 are outwardly inclined to the planes of thesides 13 immediately ahead of the sockets 32 (see FIG. 3) so that theprojections 30 are easily spread apart before they are urged partiallyinto the sockets 32.

From the foregoing it will be apparent that I have provided a simple andconveniently operable removable and replaceable tooth cap. It is asimple matter to drive said tooth cap off of the tip. A simple hammer,and drift if desired, is used to apply and remove the tooth cap, andwhen the cap is in working position the inclined faces 31 of theprojection 30 engage with the inclined bottom 33 of the socket 32 to theend that inward pressure of the cheeks 16 causes the tooth cap to beurged rearwardly into tight engagement with the tip. When the tooth capis forced onto the tip by working conditions, the wedging action of thecap on the tip tensions the cheeks 16 causing them to tend to straightenand consequently urges the projections 30 inwardly with added pressuredengagement with the socket bottom 33. Further, the projections 30 andcontacts made thereby are at the center of rotation of stress so thatthere is no tendency for looseness to develop when the parts are inworking position relative to each other.

Having described only a typical preferred form and application of myinvention, I do not wish to be limited or restricted to the specificdetails herein set forth, but Wish to reserve to myself any variationsor modifications that mayappear to those skilled in the art and fallwithin the scope of the following claims.

Having described my invention, I claim:

1. In combination, a tooth tip having a face With a recess thereinopening laterally of the tooth, a tooth cap comprising a housingengageable over the tip, and means releasably retaining the cap on thetip in a working position and including an inwardly disposed projectionon one wall of the housing and partially entering and engaged in therecess, the portionrof the housing having the projection thereon being aresilient part and the tip having an inclined face positioned to beengaged by the projection and acting to deflect the projection outwardlyaway from the tip upon rearward movement of the housing relative to thetip, said resilient part normally urging the projection into engagementwith the recess in the tip whereby the tooth cap is yieldingly pressedonto the tooth tip.

2. In combination, a tooth tip having parallel sides one having a recesstherein opening laterally of the tip, a tooth cap engageable over thetip from its forward end and having a blade seated on the tip and cheeksdepending from the blade and overlying the sides of the tip, and meansreleasably retaining the tooth cap on the tip and including, an inwardlydisposed projection on one of the cheeks and engaged in the recess, thesaid cheek being a resilient part to urge the projection inwardly intothe recess, the projection being inclined rearwardly and inwardly tocooperatively engage with the recess in the tip whereby the tooth cap isyieldingly pressed onto the tooth tip.

3. In combination, a tooth tip having parallel sides one having a recesstherein opening laterally of the tip, a tooth cap engageable over thetip from its forward end and having a blade seated on the tip and cheeksdepending from the blade and overlying the sides of the tip, and meansreleasably retaining the tooth cap on the tip and including, an inwardlydisposed projection on one of the cheeks and engaged in the recess, thesaid cheek being a resilient part to urge the projection inwardly intothe recess, the projection being inclined rearwardly and inwardly, saidrecess having an inclined bottom engaged by the inclined projection whenthe tooth cap is fully applied to the tip whereby the tooth cap isyieldingly pressed onto the tooth tip.

4. In combination, a tooth tip having parallel sides one having a recesstherein opening laterally of the tip, a tooth cap engageable over thetip and having a blade seated on the tip and having cheeks attached tothe blade and overlying the sides of the tip, and means releasablyretaining the tooth cap on the tip and including an inwardly disposedinclined projection on one of the cheeks and engaged in the recess, thesaid check being a resilient part to urge the projection inwardly intoengagement with the recess, there being a longitudinally disposed facein the tip and inclined rearwardly to terminate at the recess andadapted to engage the projection to spring it outwardly upon movement ofthe tooth cap rearward relative to the tip.

5. In combination, a tooth tip having parallel sides one having a recesstherein opening laterally of the tip,

a tooth cap engageable over the tip and having a blade seated on the tipand having cheeks attached to the blade and overlying the sides of thetip, and means releasably retaining the tooth cap on the tip andincluding an inwardly disposed inclined projection on one of the cheeksand engaged in the recess, the said cheek being a resilient part to urgethe projection inwardly into engagement with the recess, there being alongitudinally disposed channel in the tip parallel with the face of thetip supporting the tooth cap and with a bottom face inclined rearwardlyto terminate at the recess and adapted to engage the projection tospring it outwardly upon movement of the tooth cap rearward relative tothe tip.

6. In combination, a tooth tip having parallel opposite sides withrecesses therein opening laterally of the tip, a tooth cap on the tiphaving resilient cheeks overlying the said sides of the tip, and opposedinwardly disposed inclined projections on the cheeks and engaged in therecesses, the projections being adapted to cooperatively engage with therecesses when the tooth cap is fully engaged on the tip to urge thetooth cap onto the tooth tip.

7. In combination, a tooth tip having parallel opposite sides withrecesses therein opening laterally of the tip and having inclined guidefaces at the sides extending rearwardly from the forward end portion ofthe tip to points at the sides immediately forward of the recesses, atooth cap on the tip having resilient cheeks overlying the said sides ofthe tip, and opposed inwardly disposed projections on the cheeks andengaged in the recesses, the projections being adapted to cooperate withthe guide parts and be spread thereby as the cap is moved rearward andto cooperate with the recesses when the tooth cap is fully engaged onthe tip.

References Cited in the file of this patent UNITED STATES PATENTS289,797 Ball Dec. 11, 1883 1,104,366 Mahn July 21, 1914 2,055,265Swigert Sept. 22, 1936 2,124,230 Hosmer et a1. July 19, 1938 2,238,081Soberanes Apr. 15., 1941 2,431,639 Goedken Nov. 25, 1947 2,627,359Woodward Feb. 3, 1953 2,729,902 Launder Jan. 10, 1956 2,778,525 LermerJan. 22, 1957 2,807,105 Launder Sept. 24, 1957 2,846,791 Hosmer et al.Aug. 12, 1958 2,852,874 Grubb Sept. 23, 1958 2,885,801 Hill May 12, 1959FOREIGN PATENTS 87,241 Norway Feb. 18, 1956

